touch-packages team mailing list archive

[Pat McGowan <pat.mcgowan@xxxxxxxxxxxxx>]

comments from Colin

I've worked through all the images now and can see that deep suspend
sometimes fails to work completely because of a series of COMM events
that cause excessive wakeups.  Typically, in this scenario, one sees
300-700 CONN wakeup events over a 300 second interval. This either
prevents deep suspend from occurring, or wakes deep suspend almost
immediately it occurs. In this scenario, instead of a 7-10mA deep sleep,
I observe ~70-100mA being drawn.

I can trigger this on all the images I've now tested.  One easy way to
trigger this is via the USB adb connection and yanking out the cable and
then going into deep sleep without exiting adb and then going into deep
sleep. I also believe going into deep sleep while connected to adb and
then yanking out the USB cable also can cause this issue.

If I recall correctly, the CONN event relates to the USB connections and
does seem to correlate with this adb connection over USB.

This explains the difficulty I had bisecting the issue earlier on. I
believe I may have been careless in putting the device into deep sleep
with USB connected, and then disconnecting before measuring deep sleep
current with the multimeter.

So, for the anecdotal reports of battery life being reduced:

a) It may be this USB issue causing deep sleep to be interrupted by
   CONN events.

b) It may be something entirely different.

it's hard to say. But I do now have evidence that between revision 153
and 202 there are not any observable changes in deep sleep characteristics.

-- 
You received this bug notification because you are a member of Ubuntu
Touch seeded packages, which is subscribed to powerd in Ubuntu.
https://bugs.launchpad.net/bugs/1372413

Title:
  Extensive battery drain on RTM

Status in the base for Ubuntu mobile products:
  In Progress
Status in powerd package in Ubuntu:
  Confirmed

Bug description:
  Mako, RTM 1

  Since upgrading to RTM the battery life is really poor. What used to
  be a battery drain of 5-10% per hour (which is still high) is now
  10-15% per hour. Sometimes the phone runs really hot, so there seem to
  be something going on in the background that is consuming power. I
  mostly have bluetooth, GPS (which isn't always working), wifi and
  cellular on, but that's no difference from when I was running 'devel-
  proposed' with MultiROM with much less battery consumption.

  As an example, I started with a full charge at 7am. After some web
  surfing (<15 mins) and watching a couple of youtube videos (on wifi)
  battery was down to 66% at 9:15. That's 34% in just over two hours! I
  recharged again before lunch and had the phone idle until coming back
  1 hour and 45 mins later to find only 75% of battery left, this time
  without the phone running particularly hot.

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